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arXiv · 2009.03415

Exponential speedup in measuring out-of-time-ordered correlators with a single bit of quantum information

Sreeram PG·Naga Dileep Varikuti·Vaibhav Madhok
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Abstract

Out-of-time-ordered correlators (OTOC) are a quantifier of quantum information scrambling and quantum chaos. We propose an efficient quantum algorithm to measure OTOCs that provides an exponential speed-up over the best known classical algorithm provided the OTOC operator to be estimated admits an efficient gate decomposition. We also discuss a scheme to obtain information about the eigenvalue spectrum and the spectral density of OTOCs.

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Sreeram PG, Naga Dileep Varikuti, Vaibhav Madhok. 2020-09-07. Exponential speedup in measuring out-of-time-ordered correlators with a single bit of quantum information. https://doi.org/10.1016/j.physleta.2021.127257

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